Lincoln Impinger Conveyor Ovens 1100 Series - Manual (Page 45)

present at both sets of terminals,
replace control.
Conveyor Drive Check the drive sprocket on motor
(Stepper) Motor output shaft to insure that it is tight.
WITH POWER OFF: Turn the motor shaft
to check for jammed gear box. Check motor wind
ings. Ohm readings on motor terminal - 1-5, 2-6, 3-
7, 4-8, each reading should be approximately 2
ohms. If motor shaft will not turn,
replace conveyor drive (stepper) motor.
Time/Temp Display 12 VAC Power Supply Measure the transformer primary for a
inoperative (Transformer) nominal 120 VAC input, if voltage is not
present, trace wiring back to the oven
power source. Measure the secondary
output, which will normally be 12-15
VAC. Voltage across terminals 1 and 3
on the time/temp. display should read
12-15 VAC. Terminals 1-2 and 2-3
should be 1/2 the voltage reading to
1-3. If the above secondary readings
are not achieved, replace transformer.
Time/Temp Display If proper voltage is present at terminals
1, 2, and 3 on time/temp display, but
the display is not lighted, recheck all
connections for tightness. If time/temp
display is still not operating, replace
the time/temp display.
Temp display out NOTE: Time/Temp Place the thermocouple of a pyrometer
or inaccurate displays use two types into the center of the top finger. Be sure
of temperature sensors, the tip of the thermocouple is not
thermistor probe-2 touching metal. The pyrometer will
yellow wires, thermo- indicate oven temperature.
couple probe probe-1
red wire and 1 white wire
Thermistor Probe Disconnect the thermistor probe leads from the time/
temp display terminals #9 and 10. Measure the
resistance of the thermistor probe. See chart in
section D, showing probe resistance at various oven
temperature. If these readings are not achieved,
replace the thermistor probe.
Thermocouple Probe Place your pyrometer thermocouple into
the center of the top finger. Measure
D.C. millivolts at terminals 9 and 10 on
the time/temp display. See
thermocouple chart in Section D for
proper readings. Connect temperature
meter to thermocouple at terminals 9 &
10 on back of the time/temp display.
(Be sure to maintain proper polarity on
thermocouple connections.) Compare
actual oven temperature with the
reading at the time/temp display. If the
temperature readings match,
recalibrate or replace time/temp
display. If the readings do not match,
replace thermocouple probe.
Power Supply If a strange or unusual behavior is
Impinger II - 1100 Series Service Manual - International 45